1 /* IEEE754 floating point arithmetic
5 * MIPS floating point support
6 * Copyright (C) 1994-2000 Algorithmics Ltd.
8 * ########################################################################
10 * This program is free software; you can distribute it and/or modify it
11 * under the terms of the GNU General Public License (Version 2) as
12 * published by the Free Software Foundation.
14 * This program is distributed in the hope it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
23 * ########################################################################
27 #include "ieee754sp.h"
28 #include "ieee754dp.h"
30 union ieee754sp ieee754sp_fdp(union ieee754dp x)
42 case IEEE754_CLASS_SNAN:
43 ieee754_setcx(IEEE754_INVALID_OPERATION);
44 return ieee754sp_nanxcpt(ieee754sp_indef(), "fdp");
45 case IEEE754_CLASS_QNAN:
46 nan = buildsp(xs, SP_EMAX + 1 + SP_EBIAS, (u32)
47 (xm >> (DP_FBITS - SP_FBITS)));
48 if (!ieee754sp_isnan(nan))
49 nan = ieee754sp_indef();
50 return ieee754sp_nanxcpt(nan, "fdp", x);
51 case IEEE754_CLASS_INF:
52 return ieee754sp_inf(xs);
53 case IEEE754_CLASS_ZERO:
54 return ieee754sp_zero(xs);
55 case IEEE754_CLASS_DNORM:
56 /* can't possibly be sp representable */
57 ieee754_setcx(IEEE754_UNDERFLOW);
58 ieee754_setcx(IEEE754_INEXACT);
59 if ((ieee754_csr.rm == IEEE754_RU && !xs) ||
60 (ieee754_csr.rm == IEEE754_RD && xs))
61 return ieee754sp_xcpt(ieee754sp_mind(xs), "fdp", x);
62 return ieee754sp_xcpt(ieee754sp_zero(xs), "fdp", x);
63 case IEEE754_CLASS_NORM:
70 /* convert from DP_FBITS to SP_FBITS+3 with sticky right shift
72 rm = (xm >> (DP_FBITS - (SP_FBITS + 3))) |
73 ((xm << (64 - (DP_FBITS - (SP_FBITS + 3)))) != 0);
75 SPNORMRET1(xs, xe, rm, "fdp", x);